1. Field of the Invention
The present invention relates to a digital recording and/or reproducing apparatus using a recording medium. More particularly, the present invention relates to such a digital recording and/or reproducing apparatus having an interface circuit.
2. Background of the Invention
An audio recording and/or reproducing apparatus using a compact size magneto-optical disc has already been proposed by the present assignee (e.g., EP-A-473305). In recording by the use of this recording and/or reproducing apparatus, digital audio data is compressed and the compressed digital data is recorded onto a compact size magneto-optical disc having a diameter of 64 (mm), for example. In reproducing by the use of this apparatus, the compressed digital data is read out from the magneto-optical disc and is once stored into a buffer memory. Then, the data is sequentially read out from the buffer memory and is then expanded to reproduce the original digital audio data.
In this case, the magneto-optical disc has a recording capacity of about 158 Mbytes and a maximum recording or reproducing time of about 74 (min).
As this recording and/or reproducing apparatus uses the compact size magneto-optical disc having a diameter of 64 (mm) as a recording medium, the apparatus can be reduced in size and weight, and accordingly it can be conveniently used as a portable recording and/or reproducing apparatus. Further, as the recording medium is in the form of a disc, the apparatus is excellent in random accessibility in such a manner that a desired piece of music can be instantaneously selected.
In the above-mentioned recording and/or reproducing apparatus, an audio signal is recorded or reproduced in the state of digital data. Accordingly, this apparatus is considered to be used also as an external storage for storing any digital data other than digital audio data, such as computer programs, document data, and image data. Thus, the recording and/or reproducing apparatus is considered to be used not only as audio equipment but also as an external storage for a computer or the like.
The use of the recording and/or reproducing apparatus also as an external storage brings about such a convenience that a user may listen to the music with this apparatus in the way to an office and may input data from this apparatus into a computer or gather data into the apparatus in the office.
However, in adding to the recording and/or reproducing apparatus the function as the external storage for storing general digital data excluding digital audio data, the apparatus must be additionally provided with an input connector and an output connector for the general digital data. The additional provision of such input and output connectors on the outer surface of the recording and/or reproducing apparatus having a compact size is difficult from a structural point of view, or is undesirable in design.